Step-by-step answer:
Answer to problems of this kind is the reciprocal of the harmonic mean of the time required.
We need to find the average of the speeds, not the average of the time.
The respective speeds are 1/3 and 1/4.
The average of the speeds is therefore (1/3+1/4)/2 = 7/24 (harmonic mean of the time taken).
The time required is therefore the reciprocal of the unit speed,
T = 1/(7/24) = 24/7 = 3 3/7 minutes, or approximately 3.43 minutes.
Answer:
0.36x ² + 815.04x + 11,340
Step-by-step explanation:
Revenue = price × quantity
p(x) = x+14
d(x) = 0.36x + 810
Revenue = price × quantity
= (x + 14) * (0.36x + 810)
= 0.36x² + 810x + 5.04x + 11,340
= 0.36x ² + 815.04x + 11,340
Company's revenue = 0.36x ² + 815.04x + 11,340
The ratio is common, so you could write:
a1 * r^4 = a^5 (you do r^4 because there are 4 times you need to multiply by the ratio to get from a1 to a5)
Plug in the values:
3 * r^4 = 48
Divide by 3:
r^4 = 16
Take the fourth root of both sides:
r = 2
The common ratio is 2.
So your formula is y1 - y2 divided by x1 - x2. Start off with the -5, 14 as your x1 and y1 because its the biggest out of the other one. So do 14 - 2 = 12 so thats your top part and -5 - -1 which is -4 so your fraction will be 12/-4 or you have -3 as a whole number